Cargo containers have become the standard means of transportation of material by road, rail and sea. As a result of their universal usage, standards have been established with respect to the size of cargo containers and design of cargo containers so that they can be transported anywhere in the world using uniform lifting points. These uniform lifting points are required in that the cargo containers are most often lifted and moved by vehicular cranes or marine cranes which either load or unload the cargo container on a flatbed truck or railroad car or load or unload ocean-going container vessels.
The established standardized lengths are 10 feet, 20 feet, 30 feet and 40 feet. Containers of these dimensions have their lifting points comprised of lift fittings located in the corners of the containers such that the lift fitting has the benefit of two intersecting walls for support. Each wall would have horizontal support members which would be secured to the lift fitting and a vertical post at the intersection of the walls would be secured to the lift fitting. Thus, the rectangular box-like integrity of the container is maintained by the interconnection of the lift fittings and the horizontal and vertical supports.
Recent developments in the United States, Canada and Mexico have led to the development of domestic containers of nonstandard lengths in order to accommodate high volume payloads and reduce the associated cost of shipping. These nonstandard containers utilized in the domestic market are typically found in lengths of 45 feet, 48 feet or 53 feet. Despite the nonstandard length, these cargo containers still must be lifted with vehicular cranes or marine cranes which are designed to the international standard. Therefore, lifting points must be provided inboard from the ends of these nonstandard containers. These lifting points are fitted into the portal frames, but due to the fact that the frames are not supported by end walls, the necessity arises for supporting the transverse loads imposed during transportation. To overcome this problem, the lifting points and the frames are supported by large triangular gussets which stiffen the frames. However, these gussets make the internal loading of the cargo container difficult and reduce the effective cargo space within the container.
Accordingly, the present invention is directed to a lift fitting for positioning in the portal frame of nonstandard cargo containers which does not require any external stiffening and thus facilitates loading of the cargo container and increasing the effect of cargo space of the container while still maintaining the integrity of the container when being moved.